Means for stabilizing structural layer overlying earth materials in situ

ABSTRACT

Method and means for providing solid columnar support under structural layer, overlying earth materials of an earth situs. Expansible agitator means projected through relatively small diameter hole in overlying layer and expanded to agitate and loosen earth materials to define elongated body thereof of greater peripheral size than hole. Self-hardenable fluid pumped through hole into loosened earth, is allowed to harden after removal of contracted agitator means through small hole. Resultant rigid, composite column underlies area of structural layer surrounding hole for the solid support of same.

United States Patent Turzillo 151 3,685,303 51 Aug. 22, 1972 [54] MEANSFOR STABILIZING STRUCTURAL LAYER OVERLYING EARTH MATERIALS IN SITU [72]Inventor: Lee A. Turzillo, 2078 Glengary Rd.,

' Akron, Ohio 44313 [22] Filed: March 2, 1970 [21] Appl. No.: 15,355

Related US. Application Data [62] Division of Ser. No. 755,273, Aug.26,. 1968,

Pat. No. 3,530,675.

[52] US Cl. ..61/63, 61/50, 175/292 [51] Int. Cl. ..E02d 3/12, E02cl17/12, E2lh 9/21 [58] Field of Search..6/63, 5352, 53.6, 53.64, 53.66,6/35, 36; 175/292 [56] References Cited I UNITED STATES PATENTS1,384,016 7/1921 Fulkerson et a1. ..175/292 1,779,575 10/1930 Wilson..175/292 xvi. xx.

3,023,585 3/1962 Liver ..61/63 X 3,422,629 l/l969 Watts ..61/53.523,479,829 11/1969 Goodman ..61/53.6 3,365,894 l/1968 Murati....'...6l/53.6

Primary Examiner-Jacob Shapiro Attorney-William Cleland 1 1 ABSTRACTMethod and means for providing solid columnar support under structurallayer, overlying earth materials of an earth situs. Expansible agitatormeans projected through relatively small diameter hole in overlyinglayer and expanded to agitate and loosen earth materials to defineelongated body thereof of greater peripheral size than hole.Self-hardenable fluid pumped through hole into loosened earth, isallowed to harden after removal of contracted agitator means throughsmall hole. Resultant rigid, composite column underlies area ofstructural layer surrounding hole for the solid support of same.

7 Claims, 8 Drawing Figures PATENTEDmczz m2 INVENTOR. Lee A. Turzlllo Attofneq MEANS FOR STABILIZING STRUCTURAL LAYER OVERLYING EARTH MATERIALSIN SITU This is a divisional application of United States applicationSer. No. 755,273, filed Aug. 26, 1968.

BACKGROUND OF THE INVENTION existing or created in the same, so thatonly unpredictably limited areas of the subsoil could be depended uponfor any substantial degree of increased load-bearing capacity.

In one known method of treating a porous earth situs, a pilot hole wasdrilled several feet into the earth, and cleared of loose material as byflushing with water. After forcing pressurized air into the hole todrive out columnar support provided in the situs by the method theflushing water, hardenable fluid repair material was required to befilled with filler material by a series of additional operations.Moreover, the last-mentioned method was impractical, if not undulyexpensive, for providing a solid supporting column under a footer,floor, or the like, overlying an earth situs.

SUMMARY OF INVENTION In use of the method and means of the presentinvention to provide a solid columnar support under a sagging concretefloor or like slab or layer over an earth situs, a hole, smaller thanthe diameter of the required supporting column, is drilled in said slab.A boring tool provided with an expansible agitator means is then pushedthrough the hole and drilled into the earth below the slab. When theagitator means clears the slab, it is expanded, so that with requisiterotation of the tool the earth is loosened and thoroughly agitated to arequisite extent below the slab, to define a generallycylindrical-shaped body of loose earth, the operation being aided byoutward compaction of the solid by the rotated agitator means.

Hydraulic self-hardenable cement mortar or chemical mortar, underpressure, is now pumped through a passage in the tool shaft to mixthoroughly with the loosened earth. Before the mortar hardens, however,the agitator means is contracted to allow removal of the boring toolthrough the small slab opening. Upon hardening of the mixture of mortarand earth, the cylindrical body thereof overlying the hole in the slabwill support the slab, with or without elevating the slab, dependingupon the requirements. The hole in the slab can be filled in withconcrete if desired.

A general object of the present invention is to provide improved methodand means for providinga solid columnar support under sagging floor orlike slab overlying earth of a situs, without necessarily requiring useof conventional heavy drilling and pile-forming equipment, and wherebythe cost of the operation will be relatively low and the need for totalor substantial replacement of sagging slabs can be avoided.

Other objects of the invention will be manifest from the following briefdescription and the accompanying drawings.

Of the accompanying drawings:

FIG. 1 is a fragmentary vertical cross-section, partly broken away,illustrating improved means for providing solid columnar supportin anearth situs, under a floor or like slab overlying earth materials of thesitus.

FIG. 2 is'a horizontal cross-section taken substantially on the line 2-2of FIG. 1, but with the drilling tool apart from the situs. 1

FIG. 3 is a fragmentary vertical cross-section corresponding to FIG. 1,but illustrating the completed of the invention.

FIG. 4 is a view corresponding in part to FIG. 1, but illustrating useof a modified form of earth agitating means for practicing the method ofthe invention, in an initial step of the method.

FIG. 5 is a view corresponding to FIG. 4, but illustrating use of theagitating means in a more advanced stage of the method. 4

FIG. 6 is a view corresponding to FIG. 5, but illustrating use ofanother form of expansible agitator means for use in the method.

FIG. 7 is a view corresponding generally to FIGS. 4 and 6 butillustrating initial step in the method for use of further modified formof agitator means.

FIG. 8 is a view corresponding to FIG. 7 but illustrating a furtheradvanced step in the method performed by the agitator means.

Referring to FIGS. 1 and 2 of the drawings, there is illustratedsuitable apparatus for practicing the method of the present invention,as for providing reinforcing support for a sagging structural layersupported by earth E of a situs, such as a concrete floor or slab F. Asshown in FIG. 1, the improved apparatus may include a tool T includingan elongated hollow metal shaft 10, provided with an apertured closuremember 11, which may be in the form of a drill bit of known type,releasably affixed on the inner end of the shaft, as by means ofbreak-away pins 12. Shaft 10 may be of a single length of tubing, or ofa plurality of sections thereof coupled together in known manner. In anyevent, the shaft 10 may be mounted for rotation in a number of ways,such as by affixing the shaft at its upper end to a connector 13rotatably mounted in a carriage 14 of a known form of drilling rig (notshown), for rotation by 13a, for disconnecting the latter from saidsource, as

well as for inserting reinforcing devices down the holchain-dotted linesin FIG. 2. In said contracted condition, the lower end of the clockwiserotating rod 10 with agitator means 17 thereon is readily insertabledownwardly through the hole H in slab F, and into the earth below theslab. Reverse rotation against the earth materials, however, causes theblades to expand outwardly due to resistance of the earth materialsagainst concave inner portions of the blades, and continued reverserotation is effective to cause the blades to agitate and loosen theearth materials to define a cylindrical body 20 thereof greatertransverse cross-sectionthan that of hold H, as indicated bychain-dotted lines in FIG. 1. The length or depth of body 20 isdetermined by the total stroke of axial movement or reciprocation of theagitator means 17 below slab F. The requisite loosening action of theearth is aided by impaction of the soilradially beyond the circular pathof the ends of the blades 18. Free movement of the loosened earthmaterials in either direction is, in any event, facilitated by provisionof the aforementioned spaces A between the blades and shaft 10.

After formation of the earth body 20, the churning action of theexpanded blades 18 may be utilized to mix in fluid cementitiousmaterial, such as self-hardenable hydraulic cement or chemical mortar,pumped through swivel 16, shaft 10, and the apertured closure or drillbit 11. The pressurized fluid material may be retained below slab F byradially outward expansion of a rubber sleeve 22 against the wall of thehole H. For this purpose, the rubber sleeve 22 is retained on a metaltube 23, axially slidably mounted on shaft 10, between relativelymovable and fixed stop rings 24 and 25 on tube 23, respectively. A nut26 threaded on metal tube 23, is selectively rotatable against a metalsleeve 27 on tube 23, axially to compress the rubber sleeve for saidradial expansion thereof. While mixture of mortar and earth of theformed cylindrical body thereof is still fluid, the nut 26 is backedaway to permit removal of the tool with agitator means 17, in collapsedcondition, through the hole H.

In use of the apparatus described in connection with FIGS. 1 and 2, toform a hardened columnar support C beneath the concrete slab F, as shownin FIG. 3, the steps of the method may be as follows:

First, a hole H is drilled in the floor, slab or surface layer F, to beof smaller diameter than that of the required column to be formed underthe same, then the carriage 14 of a drilling rig (not shown) is moved topass the rotating rod 10, with the contracted agitator means 17 thereon,downwardly through the hole H, until all of the agitator means is workedwithin the earth beneath the slab. At this point, the rubber sleeve 27,may be expanded to seal the hole H, as shown in FIG. 1, in which casethe shaft 10 is freely rotatable and axially shiftable within the nowfixedly positioned metal tube 27.

Now, with the agitator means 17 so positioned in the earth E, thedirection of rotation of the shaft 10 is reversed to expand the blades18, as shown in full lines in FIGS. 1 and 2, by pressure of the earthagainst the concave inner sides of the blades. Continued rotation of theagitator means, while reciprocating the shaft 10, is effective to form acylindrical body 20 of loosened earth to selective depth, as indicatedin chain-dotted lines in FIG. 1, and generally of diameter substantiallygreater than the opening H in slab F. The material of the body 20 willbe more loose and porous than before due to compaction of soil into thesurrounding earth.

After the body 20 of substantially loose and porous earth has beenformed to required depth, indicated in chain-dotted lines in FIG. 1,fluid, self-hardenable cementitious material, such as hydraulic cementmortar under pressure, is pumped through the swivel connector 16, shaft10, and apertured drill bit 11, into the loosened earth material of body20 thereof formed by the agitator means. With continued rotation andvertical reciprocation of the expanded agitator means 17, as describedabove, the fluid mortar is thereby thoroughly mixed with the loosenedearth materials into a fluid, self-hardenable mass. While this mass isstill fluid, the shaft, 10 may be elevated with the agitator means incontracted condition thereon, to withdraw the same through the smallhole H in slab F. Because the fluid is supplied under pressure, theintruded body 20 may be extended to raise and/or level the slab F.

Prior to such withdrawal of the agitator means, however, rigidreinforcing devices, such as one or more elongated rigid reinforcingelements R, may be projected downwardly through the shaft 10 to knockout the bit or closure member 11. The swivel connector 16 is adapted tobe temporarily disconnected from shaft extension 13a for this purpose,as described above. After the reinforcing device or elements R have beenso positioned, the aforesaid additional pumping of fluid into theintruded body 20 is accomplished if or as necessary to elevate the slabP.

Upon hardening of the concrete body 20, it forms a solid cylindricalconcrete column or pile C, the upper end of which overlies or spans thehole H to provide requisite strong support for the slab F, as shown inFIG. 3. The hole H may be filled in with concrete to the upper level ofthe slab.

Referring to FIGS. 4 and 5, there is illustrated a modified form ofagitator means 17a mounted on shaft 10, the same including a pluralityof spiral elements 18a .of strong spring steel wire, extended between arelatively fixed collar 30 at the lower end of shaft 10 and a relativelymovable collar 31 non-rotatably carried by a sleeve 32 which is axiallyshiftable on shaft 10. Sleeve 32 is axially shiftable, as by manual orother means, radially to expand or contract the spiral elements 18a withreference to said shaft, as shown in FIGS. 5 and 4, respectively. Thatis, in the above described practice of the method of the invention, thecontracted agitator 17a is insertable through hole H, and then can beexpanded and rotated with the shaft 10, as shown in FIG. 5, to form acylindrical body 20a of loose earth, as before, with or without fluidsealing the hole H. The results are otherwise substantially as describedabove in connection with FIG. 3.

FIG. 6 is a view corresponding to FIG. 4, but showing a modified form ofagitator means 17b, wherein the spiral blades 18b are of thin, flexiblestrips of flat springy metal, adapted radially to expand and contract,generally as illustrated in FIG. 5 and 4, respectively.

FIG. 7 is a view corresponding to FIG. 4, illustrating another modifiedform of agitator means 17c, including a tapered spiral screw S on theinner end of shaft 10, adapted to pass through hole H in off-centerrelationship, progressively to pass axially staggered cutting teeth 18c,one at a time, until all of the cutting teeth are below slab F, foragitating and mixing the earth materials as before (see FIG. 5). The useis otherwise generally as for the method described above in connectionwith FIGS. 1, 2, and 3, the agitator means being removed through thehole H in the same progressive manner as described for insertionthereof.

In any of the methods described above the selfhardenable fluid materialpumped into earth body 20 may be other than hydraulic cement mortar. Forexample, well-known chemical grouts may be pumped into the earth body 20in proportions which produce very stiff gels from dilute, properlycatalyzed, aqueous solutrons.

Other modifications of the invention may be resorted to withoutdeparting from the spirit thereof or the scope of the appended claims.

What is claimed is:

1. Apparatus as for providing reinforcing support for a structure havinga point of support overlying earth material of an earth situscomprising: a boring tool including a hollow shaft, and adapted to beremovably axially insertable through an opening provided in the situs,axially to penetrate substantially below said point of support; axiallyelongated blades on said shaft selectively operable below said point toagitate and loosen the penetrated earth material upon rotation of thetool in boring direction, to define an axially elongated body of suchloosened earth material of transverse cross-section adapted to include aportion extending inwardly beneath said point of support; and means insaid tool for passage of pressurized self-hardenable cementitiousmaterial through said shaft to a point inwardly of the opening to mixwith the loosened earth, for forming the elongated body thereof into acolumn adapted to harden and support the structure at said point ofsupport; stop means being provided on said shaft to limit contraction ofsaid agitator blades to compact, curvate, coextension thereof about theshaft, and providing space of substantial flow area between the bladesand the shaft for passage of earth materials around the blades tendingto expand the same radially outwardly of the shaft upon rotation of thesame in the boring direction.

2. Apparatus as in claim 1, said agitator means including radiallyexpansible and retractable blade means.

3. Apparatus as in claim 1, wherein said agitator means includes blademeans on the tool operable to ex panded and retracted positions byrotation of the tool in the earth material, in opposite directions.

4. Apparatus as for providing reinforcing support for a structure havinga point of support overlying earth material of an earth situs,comprising; a boring tool including a shaft; a plurality of curvateagitator blades mounted on said shaft to pivot between radiallycontracted and expanded conditions about an axis coextensive with saidshaft, the shaft being insertable through an opening provided in thesitus while the agitator blades are contracted to penetrate the earthmaterial, and operable with the agitator blades radially expanded byrotation in boring direction to agitate and loosen penetrated earthmaterial beyond said point of support to define an elongated body ofsuch loosened earth material generally of sufficient cross-sectiontransversely of the axis of said shaft to penetrate below said point ofsupport; and means in said tool for passage of pressurizedself-hardenable, fluid cementitious material through said shaft inwardlyof the opening to mix with the loosened earth, for forming the elongatedbody thereof into a column adapted to harden and support the structureat said point of support; stop means being provided on said shaft tolimit contraction of said agitator blades to compact, curvate,coextension thereof about the shaft, and providing space of substantialflow area between the blades and the'shaft for passage of earthmaterials around the blades tending to expand the same radiallyoutwardly of the shaft upon rotation of the same in the boringdirection.

5. Apparatus as in claim 4, said shaft having expansive, fluid-sealingmeans thereon expansible into fluidsealing engage-ment with the wall ofsaid opening.

6. Apparatus as in claim 4, including swivel connector means on theupper end of said shaft for connecting the same to a source of supply ofsaid pressurized cementitious material.

7. Apparatus as for providing reinforcing support for a structural layeroverlying earth material of an earth situs, comprising: a boring toolincluding a shaft; agitator means including at least one axiallyextending blade of concavo-convex cross-section mounted on said shaftfor pivotal movement between a contracted condition in which the bladeconforms to the shape of the shaft, and an expanded condition in whichthe blades extend radially with respect to the shaft; said shaft therebybeing selectively insertable through an opening in the structural layerwhile the agitator means is contracted, to penetrate the earth material,and the shaft being operable with the agitator means expanded to agitateand loosen penetrated earth material beneath the structural layer todefine an elongated body of such loosened earth material generally ofgreater transverse cross-section than that of the opening, inwardly ofsaid layer; saidat least one agitator blade having opposed facesengageable with the penetrated earth material upon rotation of saidshaft in opposite directions, correspondingly to pivot the blade to saidcontracted or expanded conditions; and means in said tool for passage ofpressurized self-hardenable, fluid cementitious material through saidshaft inwardly of the opening to mix with the loosened earth, forforming the elongated body thereof into a column adapted to harden andsupport the structural layer; swivel connector means being provided onthe upper end of said shaft for connecting the same to a source ofsupply of said pressurized cementitious material, said swivel connectormeans being operable to provide passage therethrough from the exterior,as for selective insertion of elongated reinforcing means through theshaft and into the formed column while the mixed materials thereof arestill fluid; stop means being provided on said shaft to limitcontraction of said agitator blades to compact, curvate, coextensionthereof about the shaft, and providing space of substantial flow areabetween the blades and the shaft for passage of earth materials aroundthe blades tending to expand the same radially outwardly of the shaftupon rotation of the same in the boring direction.

1. Apparatus as for providing reinforcing support for a structure havinga point of support overlying earth material of an earth situscomprising: a boring tool including a hollow shaft, and adapted to beremovably axially insertable through an opening provided in the situs,axially to penetrate substantially below said point of support; axiallyelongated blades on said shaft selectively operable below said point toagitate and loosen the penetrated earth material upon rotation of thetool in boring direction, to define an axially elongated body of suchloosened earth material of transverse cross-section adapted to include aportion extending inwardly beneath said point of support; and means insaid tool for passage of pressurized self-hardenable cementitiousmaterial through said shaft to a point inwardly of the opening to mixwith the loosened earth, for forming the elongated body thereof into acolumn adapted to harden and support the structure at said point ofsupport; stop means being provided on said shaft to limit contraction ofsaid agitator blades to compact, curvate, coextension thereof about theshaft, and providing space of substantial flow area between the bladesand the shaft for passage of earth materials around the blades tendingto expand the same radially outwardly of the shaft upon rotation of thesame in the boring direction.
 2. Apparatus as in claim 1, said agitatormeans including radially expansible and retractable blade means. 3.Apparatus as in claim 1, wherein said agitator means includes blademeans on the tool operable to expanded and retracted positions byrotation of the tool in the earth material, in opposite directions. 4.Apparatus as for providing reinforcing support for a structure having apoint of support overlying earth material of an earth situs, comprising:a boring tool including a shaft; a plurality of curvate agitator bladesmounted on said shaft to pivot between radially contracted and expandedconditions about an axis coextensive with said shaft, the shaft beinginsertable through an opening provided in the situs while the agitatorblades are contracted to penetrate the earth material, and operable withthe agitator blades radially expanded by rotation in boring direction toagitate and loosen penetrated earth material beyond said point ofsupport to define an elongated body of such loosened earth materialgenerally of sufficient cross-section transversely of the axis of saidshaft to penetrate below said point of support; and means in said toolfor passage of pressurized self-hardenable, fluid cementitious materialthrough said shaft inwardly of the opening to mix with the loosenedearth, for forming the elongated body thereof into a column adapted toharden and support the structure at said point of support; stop meansbeing provided on said shaft to limit contraction of said agitatorblades to compact, curvate, coextension thereof about the shaft, andproviding space of substantial flow area between the blades and theshaft for passage of earth materials around the blades tending to expandthe same radially outwardly of the shaft upon rotation of the same inthe boring direction.
 5. Apparatus as in claim 4, said shaft havingexpansive, fluid-sealing means thereon expansible into fluid-sealingengage-ment with the wall of said opening.
 6. Apparatus as in claim 4,including swivel connector means on the upper end of said shaft forconnecting the same to a source of supply of said pressurizedcementitious material.
 7. Apparatus as for providing reinforcing supportfor a structural layer overlying earth material of an earth situs,comprising: a boring tool including a shaft; agitator means including atleast one axially extending blade of concavo-convex cross-sectionmounted on said shaft for pivotal movement between a contractedcondition in which the blade conforms to the shape of the shaft, and anexpanded condition in which the blades extend radially with respect tothe shaft; said shaft thereby being selectively insertable through anopening in the structural layer while the agitator means is contracted,to penetrate the earth material, and the shaft being operable with theagitator means expanded to agitate and loosen penetrated earth materialbeneath the structural layer to define an elongated body of suchloosened earth material generally of greater transverse cross-sectionthan that of the opening, inwardly of said layer; said at least oneagitator blade having opposed faces engageable with the penetrated earthmaterial upon rotation of said shaft in opposite directions,correspondingly to pivot the blade to said contracted or expandedconditions; and means in said tool for passage of pressurizedself-hardenable, fluid cementitious material through said shaft inwardlyof the opening to mix with the loosened earth, for forming the elongatedbody thereof into a column adapted to harden and support the structurallayer; swivel connector means being provided on the upper end of saidshaft for connecting the same to a source of supply of said pressurizedcementitious material, said swivel connector means being operable toprovide passage therethrough from the exterior, as for selectiveinsertion of elongated reinforcing means through the shaft and into theformed column while the mixed materials thereof are still fluid; stopmeans being provided on said shaft to limit contraction of said agitatorblades to compact, curvate, coextension thereof about the shaft, andproviding space of substantial flow area between the blades and theshaft for passage of earth materials around the blades tending to expandthe same radially outwardly of the shaft upon rotation of the same inthe boring direction.